The present invention relates to a new technique for retorting oil shale in situ, i.e. without removing it from the ground.
Oil shale is a naturally occurring rock formation which contains an organic material called kerogen. Laboratory tests have shown that when oil shale is heated to high temperatures in the absence of oxygen, the kerogen pyrolyzes to form hydrocarbon gases, shale oil vapors, shale oil liquids and a residual coke product. The hydrocarbon gases can be recovered as a gas while the shale oil vapors can be condensed and recovered together with shale oil liquids as shale oil. The coke and some of the shale oil liquids remain in the rock formation.